Campbell Scientific CPEC200 Closed-Path Eddy-Covariance System - Manual (Page 70)

Appendix A. CPEC200 Diagnostics
Next, compare scrub_tmpr it to the operating range (5°C to 50°C). The scrub
module will be disabled if it is too cold. The scrub module has a heater that
turns on if scrub_tmpr falls below 7°C. If the scrub module temperature is
too low, check the operation of the heater which is controlled by public
variable scrub_heat_ON. For diagnosing a problem using data saved in the
output table ts_data, the state of fans and heaters is encoded into variable
ControlBits to conserve memory space. See Appendix D, Control Bits. This
value is saved only if saving all diagnostics. Its corresponding variable
scrub_heat_Avg is saved in the averaged output tables (Flux and
Zero_Span). If the heater is on and the scrub module is too cold, check the
ambient temperature. The CPEC200 is rated for temperatures from −30°C to
50°C. If the system is started in cold weather after being turned off for several
hours, it may take up to 20 minutes to warm up to operating temperature.
The scrub module will also be disabled if it is too warm (above 50°C). The
scrub module has a fan that turns on if scrub_tmpr rises above 45°C. The fan
will stay on until the scrub temperature falls below 40°C. If the scrub module
temperature is too high, check the operation of the fan which is controlled by
public variable scrub_fan_ON. For diagnosing a problem using data saved in
the output table ts_data, the state of fans and heaters is encoded into variable
ControlBits to conserve memory space. See Appendix D, Control Bits. This
value is saved only if saving all diagnostics. Its corresponding variable,
scrub_fan_Avg, is saved in the averaged output tables (Flux and Zero_Span).
If the fan is on and the scrub module temperature is too high, check the
ambient temperature. The CPEC200 is rated for ambient temperatures between
–30°C to 50°C.
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